Table 3.

Percentage of children producing conversational language within normal limits (defined as NHz-scores above −1.0), by AOI group. Groups of children with similar durations of CI use (expressed in months) but different ages of implantation (in months) may be compared. For example, direct comparison can be made between children with 33 months of CI use at Test age 3.5 and those with 34 months of CI use at Test Age 4.5. Appropriate sets of numbers are bolded for ease of comparison. The linguistic variables considered are Number of Different Root Words (NDRW), Number of Different Bound Morphemes (NDBM), and Mean Length of Utterance in Words (MLUw).

AOI group	Age at Test = 3.5 years				Age at Test = 4.5 years
	NDRW	NDBM	MLUw	Mean mos. duration of CI use at test	NDRW	NDBM	MLUw	Mean mos. duration of CI use at test
6–11	44 %	59 %	44 %	33	67 %	78 %	63 %	45
12–18	37 %	56 %	32 %	28	34 %	37 %	34 %	40
19–24	4 %	17 %	0 %	22	21 %	21 %	13 %	34
25–30	7 %	14 %	0 %	15	14 %	0 %	7 %	27
31–38	0 %	20 %	0 %	9	10 %	10 %	10 %	22